The present disclosure relates generally to testing application updates. Typically, when an application is updated, the application update may be subject to tests by a development system before the update is incorporated into the application. While the development system is running a first set of tests on an application update, the system is preoccupied with that update and additional updates (e.g., those made by other programmers) cannot be tested until the first set of tests conclude. Each test may take a few seconds or a few minutes to run, and the full set of tests may include hundreds of tests. Tests may be run in a random order or alphabetically based on test name. Build servers may run every test in the full set of tests to ensure that the update works under all conditions.